Universal ribbon spool having a magnetic adapter with a rupturable diaphragm

ABSTRACT

There is disclosed a typewriter ribbon spool comprising a spool for receiving a spirally wound inked ribbon and an adapter received by the spool for accommodating typewriter spindles of different diameter. The adapter comprises a hub having a central passageway for receiving the typewriter spindle and a rupturable diaphragm spanning the passageway. Upon insertion of the typewriter spindle into the passageway, the diaphragm is ruptured in accordance with the size of the spindle and acts to center the spool on the spindle. The adapter hub is magnetized.

United States Patent [191 Glover Apr. 30, 1974 UNIVERSAL RIBBON SPOOL HAVING A MAGNETIC ADAPTER WITH A RUPTURABLE DIAPHRAGM [76] Inventor: William D. Glover, 1046 Banks North Rd., Fairfield, Conn. 06430 [22] Filed: July 24, 1972 [21] Appl. No.: 274,249

[52] US. Cl. 197/175 51 Int. Cl ..B41j 35/00 [58] Field of Search 197/151, 175

[56] References Cited UNITED STATES PATENTS 3,042,180 7/1962 Bishop 197/175 2,998,878 9/1961 Biedinger et al 197/175 2,873,839 2/1959 Bishop 197/175 2,925,164 2/1960 Murphy 197/175 3,002,707 10/1961 Noble 197/175 UX 3,045,800 7/1962 Landgraf 197/175 X 3,094,204 6/1963 Landgraf 197/ 175 X FOREIGN PATENTS OR APPLICATIONS 571,798 3/1933 Germany 197/175 Primary Examiner-Ernest T. Wright, Jr. Attorney, Agent, or FirmColton & Stone [57] ABSTRACT There is disclosed a typewriter ribbon spool comprising a spool for receiving a spirally wound inked ribbon and an adapter received by the spool for accommodating typewriter spindles of different diameter. The adapter comprises a hub having a central passageway for receiving the typewriter spindle and a rupturable diaphragm spanning the passageway. Upon insertion of the typewriter spindle'into the passageway, the diaphragm is ruptured in accordance with the size of the spindle, and acts to center the spool on the spindle. The adapter hub is magnetized.

13 Claims, 6 Drawing Figures fATENTEmmo-mm .FIG. 3

FIG. 6'

UNIVERSAL RIBBON SPOOL HAVING A MAGNETIC ADAPTER WITH A RUPTURABLE DIAPHRAGM BACKGROUND OF THE INVENTION This invention relates to a universal typewriter ribbon spool and adapter therefor which may be used on a variety of typewriters.

Since typewriter mechanisms have different designs for the reversing of the inked ribbon, typewriter manu facturers have designed different type spools for holding the inked ribbon. Typewriter manufacturers have not standardized the inked ribbon spools but instead have chosen different spools to suit their particular typewriter. The inked ribbon per se is fortunately fairly standard and is normally /2 inch in width and to 12 yards long.

The spool is normally two inches in over-all diameter and comprises flanges extending from a inch core to keep the ribbon wound neatly in a spiral. Although the spool diameter, width and core are fairly uniform, spools differ in two significantparts of the mechanism that holds the ribbon spool in place. The ribbon well, which receives the spool, contains a spindle ofa predetermined diameter which fits snugly into the center hole of the ribbon spool and defines an axis of rotation for the spool. The diameter of the spindle of different make typewriters varies significantly. In addition, the mechanism in the ribbon well for rotating the spool normally comprises a driving pin spaced from the spin- I dle for rotating the ribbon spool to take up the inked ribbon. The diameter of the driving pin also varies appreciably in typewriter design. Although other types of driving and centering mechanisms exist on typewriters, the central spindle and adjacent driving pin is the most common type.

It will be appreciated that there is a substantial number of typewriter manufacturers each of which produces typewriters of many different models. The number of spools particularly designed for each of these typewriters is large. The problem of providing replacements for typewriter ribbons is aggravated since the models of manufacturers change periodically and replacement spools are necessary for obsolete models which are still in use. It is accordingly apparent that the variety of inked ribbon spools that would be needed in the market to supply replacement ribbons is prohibitively large.

The prior art has recognized the desirability of providing spools which are usable as replacements on a large number of typewriters. Exemplary disclosures in the prior art are found in U. S. Pat. Nos. 2,873,839; 2,925,164; 3,042,180; Design US. Pat. No. 200,122; and Germany Pat. No. 571,798. Becuase of the problem of stocking enormous numbers of spools of various types, universal spools have met substantial commercial acceptance.

Another aspect of the invention resides in magnetically attracting an inked ribbon spool to the typewriter well. This concept is broadly disclosed in US. Pat. No. 2,998,878.

SUMMARY OF THE INVENTION It is an object of this invention to provide an inked ribbon spool and adapter therefore for providing replacement ribbons for typewriters of varying design.

It is another object of this invention to provide an inked ribbon spool and adapter therefor in which a rupturable diaphragm is forcibly inserted onto the typewriter spindle to provide an opening therethrough in accordance with the spindle diameter.

Another object of this invention is to provide an inked ribbon spool and adapter therefor comprising a hub made of a magnetic material.

In summary, one aspect of this invention comprises an inked ribbon spool and an adapter therefor including a hub having passage means extending along a central axis of the hub, rupturable diaphragm means spanning the passage means for rupturably receiving spindles of different diameter and means for cooperative engagement with the inked ribbon spool for rotating the spool.

BRIEF DESCRIPTION OF THE DRAWING FIG. 5 is a top plan view of the embodiment of FIG.

4; and

FIG. 6 is an enlarged cross sectional view of the embodiment of FIGS. 4 and 5 illustrated in juxtaposition to a typical ribbon well.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 13, there is illustrated an inked ribbon spool 10 of typical design comprising a core 12, an upper flange l4 and a lower flange 1 6 defining therebetween an inked ribbon receiving area 18. The core 12 typically comprises one or more prongs 20 upon which the end of an inked ribbon may be secured in a conventional manner. The core 12 also typically comprises two pair of spaced aligned parallel ribs 22 providing a driving connection between the spool 10 and an adapter 24 which provides important features of this invention. I t

The spool 10 and adapter 24 are illustrated in FIGS. 2 and 3 as being in operative relation with respect to a ribbon well 26 comprising a circular metallic supportv nism (not shown) of the typewriter into revolution of' the driving pin 34 about the centering spindle portion The metallic support 28 of conventional typewriters is typically made of iron or alloys thereof which are attractable by magnetic forces, the importance of which will be more fully apparent hereinafter. As previously mentioned, the two variable features of typical typewriter ribbon wells are the diameters of the centering spindle portion 36 and the driving pin 38. As will be more fully apparent hereinafter, the adapter 24 satisfactorily accommodates centering spindles and driving spool core 12 and thereby maintaining the adapter 24 within the spool 10. A notch 44 extends axially of the hub 40 for receiving the ribs 22 and provides a driving connection between the adapter 24 and the spool 10. As shown best in FIG. 2, the hub 40 comprises a flange 46 larger than the inside diameter of the core 12 to position the adapter 24 accurately within the spool 10. As is apparent from. FIG. 2, the flange 46 is captivated between the lower spool fiange l6 and the support 28 thereby ensuring that the adapter 24 is not dislodged from the core 12. Accordingly, the projections 42 act only to retain the adapter 24 in the spool during normal handling prior to use.

The hub 40 comprises a plurality of spaced driving slots 48 extending axially therethrough. The slots 48 are conveniently sized to receive the largest driving pin of typewriters using the central spindle-driving pin type ribbon advancing mechanism. The driving pin 34 may accordingly be loose in the slot 48 as indicated in FIG. 3. This is of no substantial importance since rotation of the ribbon well 26 rotates the driving pin 34 until it is in driving engagement with the slot 48 and accordingly remains in driving engagement therewith until the ribbon drive is reversed.

Extending along the central axis of the hub 40 is a passage 50 for receiving the centering spindle portion 36. The passage 50 is-spanned by one or more rupturable diaphragms 52 which divides the central passage 50 into a plurality of blind sub-passages 54, 56, 58. As will be appreciated by a comparison of FIGS. 2 and 3,

. the blind sub-passage 56 includes a portion 60 coaxial with the blind passages 54, 58 for receiving the centering spindle 36.

During insertion of the adapter 24 onto the centering spindle portion 36, the diaphragms 52 are ruptured in accordance with the spindle diameter'to closely receive and grasp the spindle portion 36. Accordingly, the adapter 24 and spool 10 are mounted for rotation about the axis of the centering spindle portion 36. It will accordingly be seen that the adapter 24 comprises means for receiving centering spindles of different diameter.

The adapter 24 is conveniently made by conventional injection molding techniques. It will be apparent that the blind sub-passages 54, 58 allow the retraction of mold parts upwardly and downwardly respectively with the adapter 24 oriented as shown in FIG. 2. The blind sub-passage 56 allows the retraction of a mold part downwardly with the adapter 24 oriented as shown in FIG. 3. Accordingly, the various mold parts which form the blind sub-passages 54, 56, 58 may be retracted in order to free the completed adapter 24 from the mold.

Another desirable feature of the adapter 24 is that it is magnetically attracted to the circular metallic sup- 4 tities of magnetizable particles. Polyethylene and Butyl rubber'are well known molding materials capable of loading to'40-50 percent filler. The quantity of magnetizable particles 62 added to the molding material should be sufficient to impart substantial magnetism to the adapter 24 while not exceeding the carrying capacity of the molding material. Any suitable magnetizable particle that is compatible with the molding material may be used. Acceptable magnetizable particles include powdered iron, magnetic iron oxide Fe o, and molybdenum disulfide. After the adapter 24 is removed from the mold, it is passed through a suitable magnetizing field to orient the particles 62 molded therein in a conventional manner. 5

It will be appreciated that the magnetized adapter 24 is attracted to the metallic support 28 of conventional typewriters so that lateral movement of the adapter 24 from the spindle portion 36 issubstantially minimized. It will be appreciated that this assists the diaphragms 52 in holding the adapter 24 centrally to the spindle 32. The magnetic attraction between the adapter 24 and the support 28 also assists in holding the spool 10 down to prevent the ribbon spool 10 from unseating.

Referring to FIGS. 4-6, there is illustrated another embodiment of the invention. The embodiment of FIGS. 4-6 is identical in many respects to the embodiment of FIGS. 1-3. For purposes of brevity, identical features in the embodiment of FIGS. 4-6 are referenced by numbers having identical digits in the tens and units position with only the differences between the embodiments being specifically discussed. The first difference between the adapters 24, 124 resides in the configuration of the driving slots 48, 148. The slots 148 are arcuate in horizontal cross section and present radially disposed driving faces for engagement with the driving pin 134.

The most important distinction between the adapters 24, 124 resides in the configuration of the rupturable diaphragms 52, 152. Each of the diaphragms 152 comprises a plurality of circular concentric sections 164, 166, 168 of decreasing thickness toward theaxis of the passage 150. This feature tends to ensure that the diaphragms 152 are ruptured from the center thereof and thereby minimizes eccentricity between the centering spindle portion 136 and the adapter 124. In all other respects, the adatpers 24, 124 are the same.

I claim:

1. An adapter for an inked ribbon spool comprising a hub having a passage extending along-a central axis of the hub, at least one diahragm spanning the passage for rupturably receiving spindles of different diameter, and means for cooperative engagement with an inked ribbon spool for rotating the spool.

2. The adapter of claim 1 wherein said one diaphragm divides the passage into a plurality of blind subpassages.

. 3. The adapter of claim 2 further comprising another diaphragm spanning the passage at a location spaced from said one diaphragm, the diaphragms dividing the passage into at least three blind sub-passages.

4. The adapter of claim 3 wherein the blind subpassages include coaxial portions.

5. The adapter of claim 3 wherein two of the blind sub-passages extend in the same direction as the hub axis and the remaining blind sub-passage is transverse thereto.

6. The adapter of claim 1 wherein said one diaphragm is of substantially constant thickness.

7. The adapter of claim 1 wherein said one diaphragm is of a predetermined thickness adjacent the central axis of the hub and increases in thickness at locations radially spaced therefrom.

8. The adapter of claim 1 wherein the hub is made of a magnetized material.

9. The adapter of claim 1 wherein said one diaphragm is imperforate.

10. An inked ribbon spool comprising a core and flanges extending radially away therefrom and defining therewith a ribbon receiving area; and an adapter for connecting the spool to typewriter ribbon wells having spindles of different diameter, comprising a hub in driving engagement with the spool and providing a passage extending along a central axis of the spool, at least one diaphragm spanningv the passage for rupturably receiving spindles of different diameter, and means for cooperative engagement with the ribbon well for rotating the hub.

11. The spool of claim 10 wherein said one diaphragm divides the passage into a plurality of blind subpassages.

12. The spool of claim 11 further comprising another diaphragm spanning the passage at a location spaced from said one diaphragm, the diaphragms dividing the passage into at least three blind sub-passages.

13. The spool of claim 10 further comprising means assisting said one diaphragm in preventing lateral movement between the spool and the ribbon well, the assisting means comprising magnetized material carried by the hub. 

1. An adapter for an inked ribbon spool comprising a hub having a passage extending along a central axis of the hub, at least one diahragm spanning the passage for rupturably receiving spindles of different diameter, and means for cooperative engagement with an inked ribbon spool for rotating the spool.
 2. The adapter of claim 1 wherein said one diaphragm divides the passage into a plurality of blind sub-passages.
 3. The adapter of claim 2 further comprising another diaphragm spanning the passage at a location spaced from said one diaphragm, the diaphragms dividing the passage into at least three blind sub-passages.
 4. The adapter of claim 3 wherein the blind sub-passages include coaxial portions.
 5. The adapter of claim 3 wherein two of the blind sub-passages extend in the same direction as the hub axis and the remaining blind sub-passage is transverse thereto.
 6. The adapter of claim 1 wherein said one diaphragm is of substantially constant thickness.
 7. The adapter of claim 1 wherein said one diaphragm is of a predetermined thickness adjacent the central axis of the hub and increases in thickness at locations radially spaced therefrom.
 8. The adapter of claim 1 wherein the hub is made of a magnetized material.
 9. The adapter of claim 1 wherein said one diaphragm is imperforate.
 10. An inked ribbon spool comprising a core and flanges extending radially away therefrom and defining therewith a ribbon receiving area; and an adapter for connecting the spool to typewriter ribbon wells having spindles of different diameter, comprising a hub in driving engagement with the spool and providing a passage extending along a central axis of the spool, at least one diaphragm spanning the passage for rupturably receiving spindles of different diameter, and means for cooperative engagement with the ribbon well for rotating the hub.
 11. The spool of claim 10 wherein said one diaphragm divides the passage into a plurality of blind sub-passages.
 12. The spool of claim 11 further comprising another diaphragm spanning the passage at a location spaced from said one diaphragm, the diaphragms dividing the passage into at least three blind sub-passages.
 13. The spool of claim 10 further comprising means assisting said one diaphragm in preventing lateral movement between the spool and the ribbon well, the assisting means comprising magnetized material carried by the hub. 